JP2016086000A - Dry film and printed wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dry film including a resin layer in which bubbles are not easily generated when laminating the resin film on a base material and which has excellent adhesion, and to provide a printed wiring board including a hardened material obtained by hardening the dry film.SOLUTION: A dry film includes a first film, a second film and a resin layer held between the first film and the second film. In the dry film, arithmetic average surface roughness Ra of a surface of the second film, coming into contact with the resin layer, is 0.1 to 1.2 μm, and a surface of the second film, coming into contact with the resin layer, is a surface laminated on the base material.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a dry film and a printed wiring board, and more specifically, a dry film having a resin layer that is less likely to generate bubbles when laminated on a substrate and has excellent adhesion, and a cure obtained by curing the dry film. The present invention relates to a printed wiring board having an object.

  Conventionally, a dry film has been used as one of means for forming a protective film or an insulating layer such as a solder resist or an interlayer insulating layer provided on a printed wiring board used in an electronic device or the like (for example, Patent Documents 1 to 3). . A dry film has a resin layer obtained by applying a curable resin composition having desired characteristics on a carrier film and then undergoing a drying process, and generally protects the surface opposite to the carrier film. The protective film for carrying out is distribute | circulating in the market in the state laminated | stacked further. After laminating the resin layer of the dry film on the substrate, the protective film and the insulating layer as described above can be formed on the printed wiring board by performing patterning and curing treatment.

Japanese Patent Laid-Open No. 7-15119 (Claims) JP 2002-162736 A (Claims) JP 2003-131366 A (Claims)

  When laminating a resin layer of a dry film on a substrate, air bubbles may be generated between the resin layer and the substrate, and the adhesion between the resin layer and the substrate may be impaired by such bubbles. there were.

  Accordingly, an object of the present invention is to provide a dry film having a resin layer that is less likely to generate bubbles when laminated on a substrate and has excellent adhesion, and a printed wiring board having a cured product obtained by curing the dry film. It is to provide.

  As a result of intensive studies in view of the above, the inventors of the present invention have found that the surface of the resin layer that comes into contact with the substrate when laminating the substrate, that is, the film provided on the laminate surface side (in many cases a protective film), The inventors have found that the problem can be solved by adjusting the roughness of the surface in contact with the resin layer, and have completed the present invention.

  In addition, when laminating the resin layer of the dry film on the base material, there was a problem of preventing an operational error that the laminate surface was mistaken, but by providing a difference in the thickness of the carrier film and the protective film, It has been found that it can be solved, and has led to the completion of another dry film of the present invention.

  That is, the dry film of the present invention is a dry film having a first film, a second film, and a resin layer sandwiched between the first film and the second film. The arithmetic average surface roughness Ra of the surface in contact with the resin layer of the second film is 0.1 to 1.2 μm, and the surface in contact with the resin layer of the second film is laminated to the substrate. It is a surface.

  In the dry film of the present invention, the thickness A of the first film is preferably larger than the thickness B of the second film.

  Another dry film of the present invention is a dry film having a first film, a second film, and a resin layer sandwiched between the first film and the second film. The surface of the second film in contact with the resin layer is a laminate surface to the substrate, and the thickness A of the first film is larger than the thickness B of the second film. Is.

  The dry film of the present invention is preferably used for vacuum laminating on a printed wiring board having a circuit.

  In the dry film of the present invention, the arithmetic average surface roughness Ra of the surface in contact with the resin layer of the first film is preferably 0.1 μm or less.

  In the dry film of the present invention, the difference (A−B) between the thickness A of the first film and the thickness B of the second film is preferably 1 μm or more.

  The cured product of the present invention is obtained by curing the resin layer of the dry film.

  The printed wiring board of the present invention comprises the cured product.

  According to the present invention, there is provided a dry film having a resin layer that is less likely to generate bubbles when laminated on a substrate and has excellent adhesion, and a printed wiring board comprising a cured product obtained by curing the dry film. can do.

It is the schematic sectional drawing which showed one Embodiment of the dry film of this invention.

<Dry film>
The dry film of the present invention is a dry film having a first film, a second film, and a resin layer sandwiched between the first film and the second film, The arithmetic average surface roughness Ra of the surface in contact with the resin layer of the second film is 0.1 to 1.2 μm, and the surface in contact with the resin layer of the second film is a laminate surface to the substrate. It is characterized by being. By defining the roughness of the surface of the second film within the range, irregularities are also formed on the surface of the resin layer in contact with the surface, thereby eliminating air bubbles when laminating the dry film to the substrate. It will be easier. The arithmetic average surface roughness Ra of the surface in contact with the resin layer of the second film is preferably 0.3 to 1.2 μm, and more preferably 0.4 to 1.2 μm. In addition, arithmetic mean surface roughness Ra means the value measured based on JISB0601.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of the dry film of the present invention. The dry film 1 includes a first film 11, a second film 12, and a resin layer 13 sandwiched between the first film 11 and the second film 12. The surface of the second film in contact with the resin layer is rough and has an arithmetic average surface roughness Ra of 0.1 to 1.2 μm.

[First film and second film]
When laminating a dry film having a resin layer sandwiched between a carrier film and a protective film, in many cases, the protective film is peeled off and the surface of the resin layer on the side in contact with the protective film is the base. Laminated to contact the material. However, the carrier film may be peeled and laminated so that the surface of the resin layer on the side in contact with the carrier film is in contact with the substrate. In the present invention, the surface in contact with the resin layer of the film (that is, the second film) on the side in contact with the surface of the resin layer that is in contact with the substrate (that is, the laminate surface) when laminating to the substrate is within the above range. What is necessary is just to have arithmetic mean surface roughness Ra. That is, the second film may be either a carrier film or a protective film. Preferably, the first film is a carrier film and the second film is a protective film.

  A carrier film has a role which supports the resin layer of a dry film, and is a film by which the below-mentioned curable resin composition is apply | coated when forming this resin layer. As the carrier film, for example, a polyester film such as polyethylene terephthalate or polyethylene naphthalate, a polyimide film, a polyamideimide film, a polyethylene film, a polytetrafluoroethylene film, a polypropylene film, a film made of a thermoplastic resin such as a polystyrene film, and Surface-treated paper or the like can be used. Among these, a polyester film can be preferably used from the viewpoints of heat resistance, mechanical strength, handleability, and the like. The thickness of the carrier film is not particularly limited, but is appropriately selected depending on the application in the range of about 10 to 150 μm. The surface on which the resin layer of the carrier film is provided may be subjected to release treatment. Further, a sputtered or ultrathin copper foil may be formed on the surface of the carrier film on which the resin layer is provided.

  The protective film is provided on the surface opposite to the carrier film of the resin layer for the purpose of preventing dust and the like from adhering to the surface of the resin layer of the dry film and improving the handleability. As the protective film, for example, a film made of a thermoplastic resin exemplified for the carrier film, surface-treated paper, and the like can be used. Among these, a polyester film, a polyethylene film, and a polypropylene film are preferable. The thickness of the protective film is not particularly limited, but is appropriately selected depending on the intended use within a range of about 10 to 150 μm. The surface on which the resin layer of the protective film is provided may be subjected to a mold release treatment.

  When using a thermoplastic resin film as the second film having the arithmetic average surface roughness Ra as described above, a filler is added to the resin when forming the film, or the film surface is blasted. Alternatively, the surface can be made into a predetermined form by hairline processing, mat coating, chemical etching, or the like, and a thermoplastic resin film having the arithmetic average surface roughness Ra can be obtained. For example, when a filler is added to the resin, the arithmetic average surface roughness Ra can be controlled by adjusting the particle size and the addition amount of the filler. In the case of blasting, the arithmetic average surface roughness Ra can be controlled by adjusting processing conditions such as blasting material and blast pressure. As the thermoplastic resin film having such a surface roughness, commercially available ones may be used. For example, Lumirror X42, Lumirror X43, Lumirror X44 manufactured by Toray Industries, Inc., Emblet PTH-12, Emblet PTH manufactured by Unitika -25, Emblet PTHA-25, Emblet PTH-38, Oji F-Tex Alphan MA-411, MA-420, E-201F, ER-440, and the like.

  The first film preferably has an arithmetic average surface roughness Ra of a surface in contact with the resin layer of 0.1 μm or less. When the thickness is 0.1 μm or less, the flatness of the surface of the resin layer after curing becomes good and the glossiness becomes good. Also, if there is a difference in the arithmetic average surface roughness Ra between the first film and the second film, it will be easier to recognize which film is visually (whether it is glossy) and prevent work mistakes. it can.

  Moreover, since it becomes easy to peel a 2nd film, it is preferable that the thickness A of a 1st film is larger than the thickness B of a 2nd film. More preferably, the difference (A−B) between the thickness A and the thickness B is 1 μm or more. Further, if there is a difference in thickness between the first film and the second film, it becomes easy to recognize which film is the touch or the appearance, and an operational error can be prevented.

  The thickness of the first film is preferably 10 to 100 μm, more preferably 15 μm or more. In the case of 10 μm or more, after laminating the dry film on the base material, even if the first film is heat-treated without being peeled off, the first film is difficult to heat shrink, and the thickness is not uniform due to the heat shrinking, It is possible to prevent deterioration in quality such that the resin layer flows along the streaks generated in the first film due to the shrinkage, and the streaks are also generated in the resin layer.

  When the resin layer of the dry film of the present invention is composed of a photosensitive resin composition, the first film is exposed to light such as the above thermoplastic resin so that the first dry film can be exposed without peeling. It is preferable to use a permeable material. In that case, the thickness of the first film is preferably 45 μm or less. When it is 45 μm or less, undercut is reduced. More preferably, it is 40 μm or less.

[Resin layer]
The resin layer of the dry film of the present invention is obtained through a drying process after applying the curable resin composition to the carrier film. The curable resin composition is not particularly limited, and a curable resin composition used for forming a protective layer or an insulating layer provided on a printed wiring board such as a conventionally known solder resist, an interlayer insulating layer, and a coverlay is used. Can do. Although the film thickness of a resin layer is not specifically limited, It is preferable that the film thickness after drying is 1-200 micrometers. In the case of the photosensitive resin layer, when it is 200 μm or less, it is possible to suppress a decrease in deep part curability. The resin layer includes a curable resin and a filler, and the blending amount of the filler is preferably 30% by mass or more based on the total amount of the resin layer of the dry film excluding the solvent. Specific examples of the curable resin composition include a photocurable resin composition containing a photopolymerization initiator, a photocurable thermosetting resin composition, a thermosetting resin composition, and a photobase generator. Photocurable resin composition, photocurable resin composition containing photoacid generator, negative photocurable resin composition and positive photocurable resin composition, alkali development type photocurable resin composition, solvent Examples include, but are not limited to, development type photocurable resin compositions, swelling release resin compositions, and dissolution release resin compositions.

(Photo-curable thermosetting resin composition)
As an example of the photocurable thermosetting resin composition, a resin composition containing a carboxyl group-containing resin, a photopolymerization initiator, and a thermosetting component will be described below.

  The carboxyl group-containing resin is a component that is cured by being polymerized or cross-linked by light irradiation, and can be rendered alkali developable by containing a carboxyl group. In addition to the carboxyl group, it is preferable to have an ethylenically unsaturated bond in the molecule from the viewpoint of photocurability and development resistance, but only a carboxyl group-containing resin having no ethylenically unsaturated double bond. May be used. When the carboxyl group-containing resin does not have an ethylenically unsaturated bond, a compound (photosensitive monomer) having one or more ethylenically unsaturated groups in the molecule is used in order to make the composition photocurable. There is a need. As the ethylenically unsaturated double bond, those derived from acrylic acid, methacrylic acid or derivatives thereof are preferable. Among the carboxyl group-containing resins, there are carboxyl group-containing resins having a copolymer structure, carboxyl group-containing resins having a urethane structure, carboxyl group-containing resins starting from an epoxy resin, and carboxyl group-containing resins starting from a phenol compound. preferable. Specific examples of the carboxyl group-containing resin include compounds listed below (which may be either oligomers or polymers).

(1) A bifunctional or higher polyfunctional epoxy resin as described later is reacted with (meth) acrylic acid, and a hydroxyl group present in the side chain is reacted with 2 such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. A carboxyl group-containing photosensitive resin to which a basic acid anhydride is added. Here, the bifunctional or higher polyfunctional epoxy resin is preferably solid.

(2) A polyfunctional epoxy resin obtained by epoxidizing a hydroxyl group of a bifunctional epoxy resin as described later with epichlorohydrin is reacted with (meth) acrylic acid, and a dibasic acid anhydride is added to the resulting hydroxyl group. A carboxyl group-containing photosensitive resin. Here, the bifunctional epoxy resin is preferably solid.

(3) An epoxy compound having two or more epoxy groups in one molecule is combined with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule, and (meth) acrylic acid or the like. Polybasic, such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid, etc., with respect to the alcoholic hydroxyl group of the reaction product obtained by reacting with a saturated carboxylic acid containing monocarboxylic acid A carboxyl group-containing photosensitive resin obtained by reacting an acid anhydride.

(4) Two or more per molecule such as bisphenol A, bisphenol F, bisphenol S, novolac type phenol resin, poly-p-hydroxystyrene, condensate of naphthol and aldehydes, condensate of dihydroxynaphthalene and aldehydes Reaction obtained by reacting an unsaturated group-containing monocarboxylic acid such as (meth) acrylic acid with a reaction product obtained by reacting a compound having a phenolic hydroxyl group with an alkylene oxide such as ethylene oxide or propylene oxide A carboxyl group-containing photosensitive resin obtained by reacting a product with a polybasic acid anhydride.

(5) A reaction product obtained by reacting a compound having two or more phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate is reacted with an unsaturated group-containing monocarboxylic acid. A carboxyl group-containing photosensitive resin obtained by reacting the resulting reaction product with a polybasic acid anhydride.

(6) Diisocyanate compounds such as aliphatic diisocyanate, branched aliphatic diisocyanate, alicyclic diisocyanate, aromatic diisocyanate, polycarbonate polyol, polyether polyol, polyester polyol, polyolefin polyol, acrylic polyol, bisphenol A type A terminal carboxyl group-containing urethane resin obtained by reacting an acid anhydride with a terminal of a urethane resin by a polyaddition reaction of a diol compound such as an alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

(7) During synthesis of a carboxyl group-containing urethane resin by a polyaddition reaction between a diisocyanate, a carboxyl group-containing dialcohol compound such as dimethylolpropionic acid or dimethylolbutyric acid, and a diol compound, a molecule such as hydroxyalkyl (meth) acrylate A carboxyl group-containing urethane resin in which a compound having one hydroxyl group and one or more (meth) acryloyl groups is added and terminally (meth) acrylated.

(8) During synthesis of a carboxyl group-containing urethane resin by polyaddition reaction of a diisocyanate, a carboxyl group-containing dialcohol compound, and a diol compound, an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate, etc. A carboxyl group-containing urethane resin obtained by adding a compound having two isocyanate groups and one or more (meth) acryloyl groups, and then terminally (meth) acrylating.

(9) Carboxy group-containing photosensitivity obtained by copolymerization of unsaturated carboxylic acid such as (meth) acrylic acid and unsaturated group-containing compound such as styrene, α-methylstyrene, lower alkyl (meth) acrylate, and isobutylene. resin.

(10) A carboxyl group obtained by reacting a difunctional acid such as adipic acid, phthalic acid or hexahydrophthalic acid with a polyfunctional oxetane resin as described later and adding a dibasic acid anhydride to the resulting primary hydroxyl group A carboxyl group formed by adding a compound having one epoxy group and one or more (meth) acryloyl groups in one molecule, such as glycidyl (meth) acrylate and α-methylglycidyl (meth) acrylate, to the containing polyester resin Contains photosensitive resin.

(11) A carboxyl group-containing photosensitive resin obtained by adding a compound having a cyclic ether group and a (meth) acryloyl group in one molecule to the carboxyl group-containing resin of any one of (1) to (10) described above.

  Here, (meth) acrylate is a generic term for acrylate, methacrylate, and mixtures thereof, and the same applies to other similar expressions.

  The acid value of the carboxyl group-containing resin is preferably 40 to 150 mgKOH / g. When the acid value of the carboxyl group-containing resin is 40 mgKOH / g or more, alkali development is improved. In addition, by setting the acid value to 150 mgKOH / g or less, it is possible to easily draw a normal resist pattern. More preferably, it is 50-130 mgKOH / g.

  It is preferable that the compounding quantity of carboxyl group-containing resin is 20-60 mass% on the resin layer whole quantity basis of the dry film except a solvent. Coating strength can be improved by setting it as 20 mass% or more. Further, when the content is 60% by mass or less, viscosity becomes appropriate and workability is improved. More preferably, it is 30-50 mass%.

  As the photopolymerization initiator used for photopolymerizing the above carboxyl group-containing resin, known ones can be used. Among them, an oxime ester photopolymerization initiator having an oxime ester group, α- Aminoacetophenone photopolymerization initiators, acylphosphine oxide photopolymerization initiators, and titanocene photopolymerization initiators are preferred. A photoinitiator may be used individually by 1 type and may be used in combination of 2 or more type.

  The amount of the oxime ester photopolymerization initiator used is preferably 0.01 to 5 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. By setting it as 0.01 mass part or more, photocurability on copper becomes more reliable and coating-film characteristics, such as chemical resistance, improve. Moreover, the light absorption in the coating-film surface is suppressed by setting it as 5 mass parts or less, and there exists a tendency for the sclerosis | hardenability of a deep part to improve. More preferably, it is 0.5-3 mass parts with respect to 100 mass parts of carboxyl group-containing resin.

  Each blending amount in the case of using an α-aminoacetophenone photopolymerization initiator or an acylphosphine oxide photopolymerization initiator is 0.01 to 15 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. preferable. By setting it as 0.01 mass part or more, photocurability on copper becomes more reliable and coating-film characteristics, such as chemical resistance, improve. Moreover, by setting it as 15 mass parts or less, sufficient reduction effect of an outgas is acquired, Furthermore, the light absorption in the cured film surface is suppressed, and the sclerosis | hardenability of a deep part improves. More preferably, it is 0.5-10 mass parts with respect to 100 mass parts of carboxyl group-containing resin.

  A photoinitiator or sensitizer may be used in combination with the above-described photopolymerization initiator. Examples of the photoinitiation assistant or sensitizer include benzoin compounds, acetophenone compounds, anthraquinone compounds, thioxanthone compounds, ketal compounds, benzophenone compounds, tertiary amine compounds, and xanthone compounds. These compounds may be used as a photopolymerization initiator in some cases, but are preferably used in combination with a photopolymerization initiator. Moreover, a photoinitiator auxiliary or a sensitizer may be used individually by 1 type, and may use 2 or more types together.

  The photocurable thermosetting resin composition contains a thermosetting component for the purpose of improving characteristics such as heat resistance and insulation reliability. Known thermosetting components such as isocyanate compounds, blocked isocyanate compounds, amino resins, maleimide compounds, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional epoxy compounds, polyfunctional oxetane compounds, episulfide resins, etc. Resin can be used. Among these, a preferable thermosetting component is a thermosetting component having a plurality of cyclic ether groups and / or cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in one molecule. There are many commercially available thermosetting components having a cyclic (thio) ether group, and various properties can be imparted depending on the structure.

  The blending amount of the thermosetting component having a plurality of cyclic (thio) ether groups in the molecule is preferably 0.3 to 2.5 equivalents, more preferably, with respect to 1 equivalent of the carboxyl group of the carboxyl group-containing resin. It is the range which becomes 0.5-2.0 equivalent. By making the amount of thermosetting component having a plurality of cyclic (thio) ether groups in the molecule 0.3 equivalent or more, no carboxyl group remains in the cured film, heat resistance, alkali resistance, electrical insulation Etc. improve. Moreover, by setting it as 2.5 equivalent or less, the low molecular weight cyclic (thio) ether group does not remain in the dry coating film, and the strength and the like of the cured coating film are improved.

  When using a thermosetting component having a plurality of cyclic (thio) ether groups in the molecule, it is preferable to contain a thermosetting catalyst. Examples of such thermosetting catalysts include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole. Imidazole derivatives such as 1- (2-cyanoethyl) -2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4- (dimethylamino) -N, N-dimethylbenzylamine, 4-methoxy-N, N -Amine compounds such as dimethylbenzylamine and 4-methyl-N, N-dimethylbenzylamine; hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide; and phosphorus compounds such as triphenylphosphine. Also, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino S-triazine derivatives such as -S-triazine and isocyanuric acid adducts and 2,4-diamino-6-methacryloyloxyethyl-S-triazine and isocyanuric acid adducts can also be used. A compound that also functions in combination with a thermosetting catalyst.

  The blending amount of the thermosetting catalyst is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts per 100 parts by mass of the thermosetting component having a plurality of cyclic (thio) ether groups in the molecule. 0.0 part by mass.

  The photocurable thermosetting resin composition may contain a photosensitive monomer in addition to the above-described carboxyl group-containing resin, photopolymerization initiator, and thermosetting component. The photosensitive monomer is a compound having one or more ethylenically unsaturated groups in the molecule. The photosensitive monomer assists photocuring of the carboxyl group-containing resin by irradiation with active energy rays.

  Examples of the compound used as the photosensitive monomer include conventionally known polyester (meth) acrylate, polyether (meth) acrylate, urethane (meth) acrylate, carbonate (meth) acrylate, epoxy (meth) acrylate, and the like. Specifically, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl acrylate; diacrylates of glycols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol, and propylene glycol; N, N-dimethylacrylamide Acrylamides such as N-methylol acrylamide and N, N-dimethylaminopropyl acrylamide; aminoalkyl acrylates such as N, N-dimethylaminoethyl acrylate and N, N-dimethylaminopropyl acrylate; hexanediol, trimethylolpropane, Polyhydric alcohols such as pentaerythritol, dipentaerythritol, tris-hydroxyethyl isocyanurate or the like Multivalent acrylates such as thyloxide adducts, propylene oxide adducts, or ε-caprolactone adducts; polyvalent acrylates such as phenoxy acrylate, bisphenol A diacrylate, and ethylene oxide or propylene oxide adducts of these phenols Acrylates; glyceryl diglycidyl ether, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, polyglycerides of glycidyl ether such as triglycidyl isocyanurate; not limited to the above, polyether polyol, polycarbonate diol, hydroxyl-terminated polybutadiene Polyurethane polyol such as polyester polyol is directly acrylated or urethane acrylate via diisocyanate It can be used by appropriately selecting from at least one selected from acrylates and melamine acrylates and methacrylates corresponding to the acrylates.

  Epoxy acrylate resin obtained by reacting polyfunctional epoxy resin such as cresol novolac type epoxy resin with acrylic acid, and hydroxyl acrylate of the epoxy acrylate resin, hydroxy acrylate such as pentaerythritol triacrylate, and diisocyanate half urethane such as isophorone diisocyanate An epoxy urethane acrylate compound reacted with a compound may be used as the photosensitive monomer. Such an epoxy acrylate resin can improve photocurability without deteriorating the touch drying property.

  The compounding amount of the compound having an ethylenically unsaturated group in the molecule used as the photosensitive monomer is preferably 5 to 100 parts by mass, more preferably 5 to 70 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. Is the ratio. By making the compounding quantity of the compound which has an ethylenically unsaturated group 5 mass parts or more, the photocurability of a photocurable thermosetting resin composition improves. Moreover, the coating-film hardness can be improved by making a compounding quantity into 100 mass parts or less.

  The photocurable thermosetting resin composition may contain other components such as a filler, a colorant, an elastomer, and a thermoplastic resin in addition to the components described above. Hereinafter, these components will also be described.

  A filler can be mix | blended with a photocurable thermosetting resin composition as needed in order to raise the physical intensity | strength etc. of the hardened | cured material obtained. As the filler, known and commonly used inorganic or organic fillers can be used. In particular, barium sulfate, spherical silica, titanium oxide, Neuburg silica clay particles, and talc are preferably used. Further, for the purpose of imparting flame retardancy, aluminum hydroxide, magnesium hydroxide, boehmite and the like can also be used. These may be used alone or in combination of two or more.

  The addition amount of the filler is preferably 500 parts by mass or less, more preferably 0.1 to 300 parts by mass, and particularly preferably 0.1 to 150 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. When the addition amount of the filler is 500 parts by mass or less, the viscosity of the photocurable thermosetting resin composition does not become too high, the printability is good, and the cured product is not easily brittle.

  The photocurable thermosetting resin composition may contain a colorant. As the colorant, known colorants such as red, blue, green, yellow, black, and white can be used, and any of pigments, dyes, and pigments may be used. However, it is preferable not to contain a halogen from the viewpoint of reducing the environmental burden and affecting the human body.

  The addition amount of the colorant is not particularly limited, but is preferably 10 parts by mass or less, particularly preferably 0.1 to 7 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin.

  Moreover, an elastomer can be mix | blended with a photocurable thermosetting resin composition for the purpose of provision of the softness | flexibility with respect to the hardened | cured material obtained, improvement of the brittleness of hardened | cured material, etc. Examples of the elastomer include a polyester elastomer, a polyurethane elastomer, a polyester urethane elastomer, a polyamide elastomer, a polyesteramide elastomer, an acrylic elastomer, and an olefin elastomer. Moreover, the resin etc. which modified the one part or all part of the epoxy resin which has various frame | skeleton with the carboxylic acid modified type butadiene- acrylonitrile rubber | gum at both ends can also be used. Furthermore, epoxy-containing polybutadiene elastomers, acrylic-containing polybutadiene elastomers, hydroxyl group-containing polybutadiene elastomers, hydroxyl group-containing isoprene elastomers and the like can also be used. One type of elastomer may be used alone, or a mixture of two or more types may be used.

  The addition amount of the elastomer is preferably 50 parts by mass or less, more preferably 1 to 30 parts by mass, and particularly preferably 5 to 30 parts by mass with respect to 100 parts by mass of the carboxyl group-containing resin. When the addition amount of the elastomer is 50 parts by mass or less, the alkali developability of the photocurable thermosetting resin composition becomes good, and the developable pot life is not easily shortened.

  In addition, the photocurable thermosetting resin composition may further contain components such as a block copolymer, an adhesion promoter, an antioxidant, and an ultraviolet absorber as necessary. As these, those known in the field of electronic materials can be used. Further, known and commonly used thickeners such as fine silica, hydrotalcite, organic bentonite, montmorillonite, at least one of defoamers and leveling agents such as silicone, fluorine, and polymer, imidazole, and thiazole At least one of known and commonly used additives such as a silane coupling agent such as a triazole or triazole, a rust inhibitor, and a fluorescent brightening agent can be blended.

  The organic solvent that can be used is not particularly limited, and examples thereof include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, petroleum solvents, and the like. be able to. More specifically, ketones such as methyl ethyl ketone, cyclohexanone, methyl butyl ketone, methyl isobutyl ketone, and methyl ethyl ketone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl Glycol ethers such as carbitol, butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, triethylene glycol monoethyl ether Class: ethyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monoethyl ester Esters such as teracetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol butyl ether acetate; ethanol, propanol, 2-methoxypropanol, n-butanol, isobutyl alcohol, isopentyl alcohol Alcohols such as ethylene glycol and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha; and N, N-dimethylformamide ( DMF), tetrachloroethylene, turpentine oil and the like. In addition, Maruzen Petrochemical Co., Ltd. Swazol 1000, Swazol 1500, Standard Petroleum Osaka Sales Co., Ltd. Solvesso 100, Solvesso 150, Sankyo Chemical Co., Ltd. Solvent # 100, Solvent # 150, Shell Chemicals Japan Co., Ltd. Shell Sol A100, Shell Sol A150 Organic solvents such as Ipsol No. 100 and Ipsol No. 150 manufactured by Idemitsu Kosan Co., Ltd. may be used. Such an organic solvent may be used individually by 1 type, and may be used as a 2 or more types of mixture.

  As a method for producing a printed wiring board using a dry film having a resin layer composed of a photocurable thermosetting resin composition, a conventionally known method may be used. For example, a printed wiring board can be manufactured by the following method. The second film is peeled from the dry film to expose the resin layer, and the photosensitive resin layer of the photosensitive dry film is laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like. Pattern exposure is performed. The first film may be peeled off either after lamination or after exposure. Thereafter, by performing alkali development, a patterned resin layer is formed on the substrate, and the patterned resin layer is cured by light irradiation or heat to form a cured film, thereby producing a printed wiring board. can do.

(Thermosetting resin composition)
As an example of the thermosetting resin composition, a resin composition containing a thermosetting component will be described below.

  The thermosetting resin component is a resin having a functional group that can be cured by heat. The thermosetting resin component is not particularly limited, and an epoxy compound, a polyfunctional oxetane compound, a compound having two or more thioether groups in the molecule, that is, an episulfide resin can be used.

  The epoxy compound is a compound having an epoxy group, and any conventionally known one can be used. Examples thereof include a bifunctional epoxy compound having two epoxy groups in the molecule and a polyfunctional epoxy compound having many epoxy groups in the molecule. In addition, a hydrogenated bifunctional epoxy compound may be used.

  Examples of the epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, and cresol novolak type. Epoxy resin, bisphenol A novolak type epoxy resin, biphenyl type epoxy resin, naphthol type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin, alicyclic epoxy resin, aliphatic chain Epoxy resin, phosphorus-containing epoxy resin, anthracene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin, fluorene type epoxy resin, aminophenol type epoxy resin Resin, amino cresol type epoxy resin, alkylphenol type epoxy resin or the like is used. These epoxy resins can be used alone or in combination of two or more.

  The epoxy compound may be a solid epoxy resin, a semi-solid epoxy resin, or a liquid epoxy resin. In this specification, a solid epoxy resin refers to an epoxy resin that is solid at 40 ° C., and a semi-solid epoxy resin refers to an epoxy resin that is solid at 20 ° C. and is liquid at 40 ° C. Means an epoxy resin that is liquid at 20 ° C. Judgment of liquid state shall be made in accordance with the second “Liquid Confirmation Method” of the Ministerial Ordinance on Dangerous Goods Testing and Properties (Ministry of Local Government Ordinance No. 1 of 1989).

  A thermosetting resin component can be used individually by 1 type or in combination of 2 or more types. The compounding amount of the thermosetting resin component is preferably 10 to 50% by mass, more preferably 10 to 40% by mass, and more preferably 10 to 35% by mass based on the total amount of the resin layer of the dry film excluding the solvent. % Is even more preferred. Moreover, since the glass transition temperature (Tg) and crack resistance of hardened | cured material become more favorable, the compounding quantity of a liquid epoxy resin in the case of mix | blending a liquid epoxy resin becomes 0-45 per thermosetting resin component total mass. It is preferably mass%, more preferably 0 to 30 mass%, and particularly preferably 0 to 5 mass%.

  A filler can be mix | blended with a thermosetting resin composition as needed in order to raise the physical intensity | strength etc. of the hardened | cured material obtained. Although there is no restriction | limiting in particular as a filler, For example, the filler illustrated with the said photocurable thermosetting resin composition is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

  Although there is no restriction | limiting in particular as an organic solvent which can be used, For example, the organic solvent illustrated with the said photocurable thermosetting resin composition is mentioned. An organic solvent may be used individually by 1 type, and may be used as a 2 or more types of mixture.

  The thermosetting resin composition can contain a curing agent. Examples of the curing agent include phenol resins, polycarboxylic acids and acid anhydrides thereof, cyanate ester resins, active ester resins, maleimide compounds, and alicyclic olefin polymers. A hardening | curing agent can be used individually by 1 type or in combination of 2 or more types.

  In the curing agent, the ratio of the functional group capable of thermosetting reaction, such as the epoxy group of the thermosetting resin component, to the functional group in the curing agent that reacts with the functional group is the functional group of the curing agent / thermosetting. It is preferable to blend in such a ratio that the functional group capable of reacting (equivalent ratio) = 0.2-2. By setting the functional group of the curing agent / functional group capable of thermosetting reaction (equivalent ratio) within the above range, roughening of the film surface in the desmear process can be prevented. More preferably, the functional group of the curing agent / functional group capable of thermosetting reaction (equivalent ratio) = 0.2 to 1.5, and more preferably the functional group of the curing agent / functional group capable of thermosetting reaction ( Equivalent ratio) = 0.3 to 1.0.

  The thermosetting resin composition can further contain a thermoplastic resin in order to improve the mechanical strength of the resulting cured film. The thermoplastic resin is preferably soluble in a solvent. When it is soluble in the solvent, the flexibility of the dry film is improved, and the generation of cracks and powder falling can be suppressed. As the thermoplastic resin, use is made of thermoplastic polyhydroxy polyether resin, phenoxy resin that is a condensate of epichlorohydrin and various bifunctional phenolic compounds, or hydroxyl group of hydroxy ether part present in the skeleton of various acid anhydrides and acid chlorides. And esterified phenoxy resin, polyvinyl acetal resin, polyamide resin, polyamideimide resin, block copolymer and the like. A thermoplastic resin can be used individually by 1 type or in combination of 2 or more types.

  The blending amount of the thermoplastic resin is 0.5 to 20% by mass, preferably 0.5 to 10% by mass, based on the total amount of the resin layer excluding the solvent. When the blending amount of the thermoplastic resin is out of the above range, it becomes difficult to obtain a uniform roughened surface state.

  Furthermore, the thermosetting resin composition can contain rubber-like particles as necessary. Examples of such rubber-like particles include polybutadiene rubber, polyisopropylene rubber, urethane-modified polybutadiene rubber, epoxy-modified polybutadiene rubber, acrylonitrile-modified polybutadiene rubber, carboxyl group-modified polybutadiene rubber, acrylonitrile butadiene rubber modified with a carboxyl group or a hydroxyl group, and These crosslinked rubber particles, core-shell type rubber particles, and the like can be mentioned, and one kind can be used alone or two or more kinds can be used in combination. These rubber-like particles are added to improve the flexibility of the resulting cured film, improve crack resistance, enable surface roughening treatment with an oxidizing agent, and improve adhesion strength with copper foil, etc. Is done.

  The average particle size of the rubber-like particles is preferably in the range of 0.005 to 1 μm, and more preferably in the range of 0.2 to 1 μm. The average particle diameter of the rubber-like particles in the present invention can be measured using a dynamic light scattering method. For example, rubber-like particles are uniformly dispersed in an appropriate organic solvent by ultrasonic waves, etc., and using FPRA-1000 (manufactured by Otsuka Electronics Co., Ltd.), the particle size distribution of the rubber-like particles is created on a mass basis and the median diameter is The average particle size can be measured.

  The compounding amount of the rubber-like particles is preferably 0.5 to 10% by mass and more preferably 1 to 5% by mass based on the total amount of the resin layer excluding the solvent. In the case of 0.5% by mass or more, crack resistance is obtained, and the adhesion strength with a conductor pattern or the like can be improved. When the content is 10% by mass or less, the coefficient of thermal expansion (CTE) decreases, the glass transition temperature (Tg) increases, and the curing characteristics are improved.

  The resin layer of the dry film of the present invention can contain a curing accelerator. The curing accelerator is for accelerating the thermosetting reaction, and is used for further improving properties such as adhesion, chemical resistance, and heat resistance. Specific examples of such curing accelerators include imidazole and derivatives thereof; guanamines such as acetoguanamine and benzoguanamine; diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, Polyamines such as melamine and polybasic hydrazides; organic acid salts and / or epoxy adducts thereof; amine complexes of boron trifluoride; ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4- Triazine derivatives such as diamino-6-xylyl-S-triazine; trimethylamine, triethanolamine, N, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) Amines such as lamin, 2,4,6-tris (dimethylaminophenol), tetramethylguanidine, m-aminophenol; polyphenols such as polyvinylphenol, polyvinylphenol bromide, phenol novolac, alkylphenol novolac; tributylphosphine, tri Organic phosphines such as phenylphosphine and tris-2-cyanoethylphosphine; phosphonium salts such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide and hexadecyltributylphosphonium chloride; benzyltrimethylammonium chloride and phenyltributylammonium chloride Quaternary ammonium salts such as polybasic acid anhydrides; diphenyliodonium tetrafluoroboroate, triphenyl Photocationic polymerization catalyst such as sulfonium hexafluoroantimonate and 2,4,6-triphenylthiopyrylium hexafluorophosphate; styrene-maleic anhydride resin; equimolar reaction product of phenyl isocyanate and dimethylamine, tolylene diisocyanate, Conventionally known curing accelerators such as an equimolar reaction product of an organic polyisocyanate such as isophorone diisocyanate and dimethylamine, and a metal catalyst can be used. Among the curing accelerators, phosphonium salts are preferred because BHAST resistance is obtained.

  A hardening accelerator can be used individually by 1 type or in mixture of 2 or more types. The use of a curing accelerator is not essential, but particularly when it is desired to accelerate curing, it can be used preferably in the range of 0.01 to 5 parts by mass with respect to 100 parts by mass of the thermosetting resin component. In the case of a metal catalyst, 10 to 550 ppm is preferable in terms of metal with respect to 100 parts by mass of the thermosetting resin component, and 25 to 200 ppm is preferable.

  The thermosetting resin composition may further include, as necessary, conventionally known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, asbestos, Conventionally known thickeners such as olben, benton and fine silica, adhesion of antifoaming and / or leveling agents such as silicones, fluorines and polymers, thiazoles, triazoles and silane coupling agents Conventionally known additives such as imparting agents, flame retardants, titanates, and aluminum can be used.

  As a method for producing a printed wiring board using a dry film having a resin layer made of a thermosetting resin composition, a conventionally known method may be used. For example, a printed wiring board can be manufactured by the following method. The second film is peeled off from the dry film, heat laminated to the circuit board on which the circuit pattern is formed, and then thermally cured. The heat curing may be performed in an oven or by a hot plate press. When laminating or hot plate pressing the substrate on which the circuit is formed and the dry film of the present invention, the copper foil or the substrate on which the circuit is formed can be laminated simultaneously. A printed wiring board can be manufactured by forming a pattern or a via hole by laser irradiation or drilling at a position corresponding to a predetermined position on the substrate on which the circuit pattern is formed, and exposing the circuit wiring. At this time, if there is a component (smear) that cannot be completely removed on the circuit wiring in the pattern or via hole, desmear processing is performed. The first film may be peeled off after lamination, after heat curing, after laser processing, or after desmear treatment.

(Photobase generator-containing composition)
As an example of the photobase generator-containing composition, a composition containing an alkali-developable resin, a thermally reactive component, and a photobase generator will be described below.

  The alkali-developable resin is a resin that contains one or more functional groups among phenolic hydroxyl groups, thiol groups, and carboxyl groups and that can be developed with an alkaline solution, preferably a compound having two or more phenolic hydroxyl groups, carboxyl Examples thereof include a group-containing resin, a compound having a phenolic hydroxyl group and a carboxyl group, and a compound having two or more thiol groups.

  As the carboxyl group-containing resin, a known resin containing a carboxyl group can be used. Due to the presence of the carboxyl group, the resin composition can be made alkali developable. In addition to the carboxyl group, a compound having an ethylenically unsaturated bond in the molecule may be used, but in the present invention, the carboxyl group-containing resin is a carboxyl group having no ethylenically unsaturated double bond. It is preferable to use only the containing resin.

  As specific examples of the carboxyl group-containing resin that can be used in the present invention, in addition to (1) to (11) listed as the carboxyl group-containing resins contained in the photocurable thermosetting resin composition, The compounds as listed (any of oligomers and polymers) may be mentioned.

  (12) Diisocyanates such as aliphatic diisocyanates, branched aliphatic diisocyanates, alicyclic diisocyanates, and aromatic diisocyanates; carboxyl group-containing dialcohol compounds such as dimethylolpropionic acid and dimethylolbutanoic acid, polycarbonate polyols, and polyethers A carboxyl group-containing urethane resin by a polyaddition reaction of a diol compound such as a polyol, a polyester-based polyol, a polyolefin-based polyol, an acrylic polyol, a bisphenol A-based alkylene oxide adduct diol, a compound having a phenolic hydroxyl group and an alcoholic hydroxyl group.

  (13) Diisocyanate and bifunctional epoxy resin such as bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bixylenol type epoxy resin, biphenol type epoxy resin ( Carboxyl group-containing urethane resin by polyaddition reaction of (meth) acrylate or its partial acid anhydride modified product, carboxyl group-containing dialcohol compound and diol compound.

  (14) During the synthesis of the resin of the above (12) or (13), a compound having one hydroxyl group and one or more (meth) acryloyl groups in a molecule such as hydroxyalkyl (meth) acrylate is added. (Meth) acrylic carboxyl group-containing urethane resin.

  (15) During the synthesis of the resin of the above (12) or (13), one isocyanate group and one or more (meth) acryloyl groups are introduced into the molecule, such as an equimolar reaction product of isophorone diisocyanate and pentaerythritol triacrylate. The carboxyl group-containing urethane resin which added the compound which has and was terminally (meth) acrylated.

  (16) A polyfunctional epoxy resin as described above is reacted with a saturated monocarboxylic acid, and a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride or hexahydrophthalic anhydride is added to the hydroxyl group present in the side chain. Carboxyl group-containing resin. Here, the polyfunctional epoxy resin is preferably solid.

  (17) A carboxyl group-containing polyester resin obtained by reacting a polyfunctional oxetane resin as described later with a dicarboxylic acid and adding a dibasic acid anhydride to the resulting primary hydroxyl group.

  (18) A carboxyl group-containing resin obtained by reacting a polybasic acid anhydride with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide. .

  (19) A saturated monocarboxylic acid is reacted with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with an alkylene oxide such as ethylene oxide or propylene oxide. A carboxyl group-containing resin obtained by reacting a basic acid anhydride.

  (20) A reaction product obtained by reacting a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate, with a saturated monocarboxylic acid. A carboxyl group-containing resin obtained by reacting with a polybasic acid anhydride.

  (21) A carboxyl group obtained by reacting a polybasic acid anhydride with a reaction product obtained by reacting a compound having a plurality of phenolic hydroxyl groups in one molecule with a cyclic carbonate compound such as ethylene carbonate or propylene carbonate. Containing resin.

  (22) An epoxy compound having a plurality of epoxy groups in one molecule, a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol, and a saturated monocarboxylic acid React with acid and react with polybasic acid anhydrides such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid etc. to the alcoholic hydroxyl group of the resulting reaction product Carboxyl group-containing resin obtained by allowing

  (23) reacting an epoxy compound having a plurality of epoxy groups in one molecule with a compound having at least one alcoholic hydroxyl group and one phenolic hydroxyl group in one molecule such as p-hydroxyphenethyl alcohol; Carboxyl groups obtained by reacting polybasic acid anhydrides such as maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, adipic acid with the alcoholic hydroxyl group of the obtained reaction product Containing resin.

  (24) One epoxy group and one or more (meth) acryloyl in a molecule such as glycidyl (meth) acrylate, α-methylglycidyl (meth) acrylate and the like in any one of the resins (12) to (23) above A carboxyl group-containing resin formed by adding a group-containing compound.

Such an alkali-developable resin has a large number of carboxyl groups, hydroxyl groups, and the like in the side chain of the backbone polymer, so that development with an alkaline aqueous solution becomes possible.
In addition, the hydroxyl group equivalent or carboxyl group equivalent of the alkali developable resin is 80 to 900 g / eq. And more preferably 100 to 700 g / eq. It is. Hydroxyl group equivalent or carboxyl group equivalent is 900 g / eq. In the following cases, adhesion of the pattern layer is obtained, and alkali development becomes easy. On the other hand, the hydroxyl group equivalent or the carboxyl group equivalent is 80 g / eq. The above case is preferable because dissolution of the light-irradiated portion by the developer is suppressed, and a normal resist pattern can be easily drawn without losing lines more than necessary. Further, it is preferable that the carboxyl group equivalent or the phenol group equivalent is large because development is possible even when the content of the alkali-developable resin is small.

  The acid value of the alkali developable resin is preferably 40 to 150 mgKOH / g. When the acid value of the alkali-developable resin is 40 mgKOH / g or more, alkali development is improved. In addition, by setting the acid value to 150 mgKOH / g or less, it is possible to easily draw a normal resist pattern. More preferably, it is 50-130 mgKOH / g.

  The blending amount of the alkali-developable resin is preferably 20 to 60% by mass based on the total amount of the resin layer of the dry film excluding the solvent. Coating strength can be improved by setting it as 20 mass% or more. Further, when the content is 60% by mass or less, the viscosity becomes appropriate and the coating property is improved. More preferably, it is 30-50 mass%.

  The thermoreactive compound is a resin having a functional group that can be cured by heat. An epoxy resin, a polyfunctional oxetane compound, etc. are mentioned.

  The epoxy resin is a resin having an epoxy group, and any known one can be used. Examples thereof include a bifunctional epoxy resin having two epoxy groups in the molecule, and a polyfunctional epoxy resin having many epoxy groups in the molecule. In addition, a hydrogenated bifunctional epoxy compound may be used.

  The epoxy resin preferably has an epoxy equivalent of 100 or more. When the epoxy equivalent is 100 or more, the warp of the cured film is suppressed, and the developability is excellent even when left under high humidity for a long time.

  The blending amount of the heat-reactive compound is preferably such that the equivalent ratio to the alkali-developable resin (heat-reactive group: alkali-developable group) is 1: 0.1 to 1:10, and 1: 0 More preferably, it is 2 to 1: 8. When the ratio is within such a range, the development is good.

  One or more photobase generators can function as a catalyst for the addition reaction of the above-mentioned thermoreactive compound when the molecular structure is changed by irradiation with light such as ultraviolet rays or visible light, or when the molecule is cleaved. It is a compound that produces a basic substance. Examples of basic substances include secondary amines and tertiary amines.

  Examples of photobase generators include α-aminoacetophenone compounds, oxime ester compounds, acyloxyimino groups, N-formylated aromatic amino groups, N-acylated aromatic amino groups, nitrobenzyl carbamate groups, and alkoxyoxybenzyl carbamates. And compounds having a substituent such as a group.

  The said photobase generator may be used individually by 1 type, and may be used in combination of 2 or more type. The compounding quantity of the photobase generator in a photobase generator containing composition becomes like this. Preferably it is 1-50 mass parts with respect to 100 mass parts of thermoreactive compounds, More preferably, it is 1-40 mass parts. The amount of 1 part by mass or more is preferable because development is easy.

  In the photobase generator-containing composition, a filler can be blended as necessary in order to increase the physical strength of the obtained cured product. Although there is no restriction | limiting in particular as a filler, For example, the filler illustrated with the said photocurable thermosetting resin composition is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

  Although there is no restriction | limiting in particular as an organic solvent which can be used, For example, the organic solvent illustrated with the said photocurable thermosetting resin composition is mentioned. An organic solvent may be used individually by 1 type, and may be used as a 2 or more types of mixture.

If necessary, the photobase generator-containing composition may further contain components such as a mercapto compound, an adhesion promoter, an antioxidant, and an ultraviolet absorber. As these, those known in the field of electronic materials can be used.
The photobase generator-containing composition includes a known and commonly used thickener such as finely divided silica, hydrotalcite, organic bentonite, and montmorillonite, an antifoaming agent such as silicone, fluorine, and polymer. Or well-known and usual additives, such as a leveling agent, a silane coupling agent, a rust preventive agent, can be mix | blended.

  As a method for producing a printed wiring board using a dry film having a resin layer made of a photobase generator-containing composition, a conventionally known method may be used. For example, a printed wiring board can be manufactured by the following method. The second film is peeled from the dry film to expose the resin layer, and the dry film is laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like. After that, the photobase generator contained in the photobase generator-containing resin composition is activated by negative pattern light irradiation to cure the light irradiated portion, and the negative portion is removed by alkali development to remove the unirradiated portion. A pattern layer of the mold can be formed. The first film may be peeled off either after lamination or after exposure. Moreover, it is preferable to heat a resin layer after light irradiation and before image development. Thereby, a resin layer can fully be hardened and the pattern layer excellent in the hardening characteristic can be obtained. The heating after light irradiation and before development is preferably a temperature at which the unirradiated part is not thermally cured. Moreover, it is preferable to perform thermosetting (post-cure) after development. After development, ultraviolet curing may be performed to activate the photobase generator remaining without being activated at the time of light irradiation, and then heat curing (post-cure) may be performed.

(Positive photosensitive thermosetting resin composition)
As an example of the positive photosensitive thermosetting resin composition, a resin composition containing a compound that generates a carboxyl group by light irradiation will be described below.

  Among the compounds that generate a carboxyl group by light irradiation, it is preferable to use a naphthoquinonediazide compound. Naphthoquinone diazide compounds are conventionally used in systems that suppress alkali solubility such as carboxyl groups by forming complexes with carboxyl groups and phenolic hydroxyl groups, and then dissociate the complex by subsequent light irradiation to develop alkali solubility. ing. In this case, if the naphthoquinone diazide compound remains in the film, the complex may be dissociated by light irradiation and the solubility may be expressed. Therefore, in the semiconductor field and the like, the remaining naphthoquinone diazide compound will eventually fly at a high temperature. It was removed by that. However, in the field of printed wiring boards, such a high temperature cannot be applied, and since it cannot be used as a permanent coating film from the viewpoint of stability, a naphthoquinone diazide compound has not been actually used. In the present invention, when a naphthoquinone diazide compound is used as a compound that generates a carboxyl group by light irradiation, the naphthoquinone diazide compound remaining in the unexposed part is incorporated into the crosslinked structure during the thermosetting reaction and is stabilized, The film toughness, that is, the bending resistance and the electrical characteristics can be improved without causing the conventional removal problem. In particular, naphthoquinone diazide compound as a compound that generates a carboxyl group by light irradiation is used in combination with polyamideimide resin and thermosetting component to ensure good developability and resolution while ensuring flexibility. This is preferable because it can be improved.

  Specific examples of the naphthoquinone diazide compound include, for example, naphthoquinone diazide adduct of tris (4-hydroxyphenyl) -1-ethyl-4-isopropylbenzene (for example, TS533, TS567, TS583, TS593 manufactured by Sanpo Chemical Laboratory Co., Ltd.). ), Naphthoquinonediazide adducts of tetrahydroxybenzophenone (for example, BS550, BS570, BS599 manufactured by Sanpo Chemical Laboratory Co., Ltd.) and the like can be used.

  In the positive photosensitive thermosetting resin composition, a filler can be blended as necessary in order to increase the physical strength of the obtained cured product. Although there is no restriction | limiting in particular as a filler, For example, the filler illustrated with the said photocurable thermosetting resin composition is mentioned. A filler may be used individually by 1 type and may be used as a mixture of 2 or more types.

  Specific examples of the alkali-developable resin contained in the positive photosensitive thermosetting resin composition include the carboxyl group-containing resin exemplified in the photocurable thermosetting resin composition, and the photobase generator-containing composition. Examples thereof include alkali developable resins.

  The positive photosensitive thermosetting resin composition may contain a thermosetting component for the purpose of improving characteristics such as heat resistance and insulation reliability. Known thermosetting components such as isocyanate compounds, blocked isocyanate compounds, amino resins, maleimide compounds, benzoxazine resins, carbodiimide resins, cyclocarbonate compounds, polyfunctional epoxy compounds, polyfunctional oxetane compounds, episulfide resins, etc. Resin can be used. Among these, a preferable thermosetting component is a thermosetting component having a plurality of cyclic ether groups and / or cyclic thioether groups (hereinafter abbreviated as cyclic (thio) ether groups) in one molecule. There are many commercially available thermosetting components having a cyclic (thio) ether group, and various properties can be imparted depending on the structure.

  The blending amount of the thermosetting component having a plurality of cyclic (thio) ether groups in the molecule is preferably 0.3 to 2.5 equivalents, more preferably 1 equivalent to the carboxyl group of the carboxyl group-containing photosensitive resin. Is in the range of 0.5 to 2.0 equivalents. By making the amount of thermosetting component having a plurality of cyclic (thio) ether groups in the molecule 0.3 equivalent or more, no carboxyl group remains in the cured film, heat resistance, alkali resistance, electrical insulation Etc. improve. Moreover, by setting it as 2.5 equivalent or less, the low molecular weight cyclic (thio) ether group does not remain in the dry coating film, and the strength and the like of the cured coating film are improved.

  Although there is no restriction | limiting in particular as an organic solvent which can be used, For example, the organic solvent illustrated with the said photocurable thermosetting resin composition is mentioned. An organic solvent may be used individually by 1 type, and may be used as a 2 or more types of mixture.

  The positive photosensitive thermosetting resin composition may contain other components such as a block copolymer, a filler, a colorant, an elastomer, and a thermoplastic resin in addition to the components described above. In addition, the positive photosensitive thermosetting resin composition may further contain components such as an adhesion promoter, an antioxidant, and an ultraviolet absorber as necessary. As these, those known in the field of electronic materials can be used. Further, known and commonly used thickeners such as fine silica, hydrotalcite, organic bentonite, montmorillonite, at least one of defoamers and leveling agents such as silicone, fluorine, and polymer, imidazole, and thiazole At least one of known and commonly used additives such as a silane coupling agent such as a triazole or triazole, a rust inhibitor, and a fluorescent brightening agent can be blended.

  As a method for producing a printed wiring board using a dry film having a resin layer made of a positive photosensitive thermosetting resin composition, a conventionally known method may be used. For example, a printed wiring board can be manufactured by the following method. The second film is peeled from the dry film, the resin layer is exposed, and the dry film is laminated on the substrate on which the circuit pattern is formed using a vacuum laminator or the like. Thereafter, the resin layer is irradiated with light in a positive pattern, the resin layer is alkali-developed, and the light irradiation portion is removed, whereby a positive pattern layer can be formed. The first film may be peeled off either after lamination or after exposure. Moreover, a printed wiring board can be manufactured by heat-hardening (post-cure) a resin layer after image development, and hardening | curing an unirradiated part. In the positive photosensitive thermosetting resin composition, a composition that is soluble in an alkali developer is changed by an acid generated by light irradiation, so that a positive pattern can be formed by alkali development.

  Another dry film of the present invention is a dry film having a first film, a second film, and a resin layer sandwiched between the first film and the second film, The surface of the second film in contact with the resin layer is a laminate surface to the base material, and the thickness A of the first film is larger than the thickness B of the second film. It is. Regarding the first film, the second film, and the resin layer of the other dry film of the present invention, the first film, the second film, and the resin described in the dry film of the present invention, respectively. Same as layer. In another dry film of the present invention, the arithmetic average surface roughness Ra of the surface in contact with the resin layer of the second film is preferably 0.1 to 1.2 μm, and 0.3 to 1.2 μm. It is more preferable that it is 0.4 to 1.2 μm.

  The dry film of the present invention and the other dry film of the present invention can be preferably used for the formation of a permanent protective film for a printed wiring board, and in particular, for the formation of a solder resist layer, an interlayer insulating layer, and a coverlay for a flexible printed wiring board. It can be preferably used. In addition, the dry film of the present invention can be suitably used for a printed wiring board having a fine pitch wiring pattern such as a package substrate having a large influence of air bubbles. Furthermore, the dry film of the present invention can also be suitably used when a vacuum laminate in which bubbles are likely to be generated is employed as the dry film laminating method. You may form a wiring board by bonding a wiring using the dry film of this invention, and the other dry film of this invention. It can also be used as a sealing resin for semiconductor chips.

  EXAMPLES Hereinafter, although an Example, a comparative example, and a test example of this invention are shown and this invention is demonstrated concretely, it cannot be overemphasized that this invention is not what is limited to the following Example. In the following description, “parts” and “%” are all based on mass unless otherwise specified.

(Adjustment of curable compositions 1-12)
The components shown in Tables 1 and 2 below were blended, stirred, and kneaded and dispersed with a three-roll mill to adjust the viscosity to 0.5 to 20 dPa · s (rotary viscometer 5 rpm, 25 ° C.).

＊１：日本化薬社製ＺＦＲ−１１２４（ビスフェノールＦ構造の多官能エポキシ樹脂を使用した感光性カルボキシル基含有樹脂）
＊２：ＤＩＣ社製ＥＭＧ−１０１５（カルボキシル基含有ポリイミド樹脂、溶液酸価：８６３ｍｇＫＯＨ／ｇ、固形分５０％）
＊３：新中村化学工業社製Ａ−ＤＣＰ（トリシクロデカンジメタノールジアクリレート）
＊４：三菱化学社製ｊＥＲ８２８（ビスフェノールＡ型エポキシ樹脂；エポキシ当量１８０ｇ／ｅｑ）
＊５：ＤＩＣ社製ＨＰ−７２００Ｌ（ジシクロペンタジエン型エポキシ樹脂；エポキシ当量２４７ｇ／ｅｑ）
＊６：明和化成社製ＨＦ−１Ｍ（フェノールノボラック樹脂；水酸基当量１０６ｇ／ｅｑ）
＊７：新日化エポキシ製造社製ＳＮ−４８５（ナフト−ルアラルキル樹脂；水酸基当量２１０ｇ／ｅｑ）
＊８：ＤＩＣ社製ＬＡ−３０１８（ノボラック樹脂；水酸基当量７５ｇ／ｅｑ）
＊９：ＤＩＣ社製ＬＡ−７０５４（ノボラック樹脂；水酸基当量１２５ｇ／ｅｑ）
＊１０：ロンザジャパン社製ＰＴ−３０（フェノールノボラック型多官能シアネートエステル；シアネート当量１２４ｇ／ｅｑ）
＊１１：ＤＩＣ社製ＨＰＣ−８０００−６５Ｔ（活性エステル樹脂；当量２２３ｇ／ｅｑ）
＊１２：ＢＡＳＦジャパン社製イルガキュア３６９（α−アミノアセトフェノン系光重合開始剤）
＊１３：堺化学社製Ｂ−３０（硫酸バリウム）
＊１４：アドマテックス社製ＳＯ−Ｃ２（シリカ）
＊１５：昭和電工社製ハイジライトＨ−４２Ｔ（水酸化アルミニウム）
＊１６：大和化成社製ＢＭＩ−２３００（フェニルメタンマレイミドの縮合物；軟化点７０〜１４５℃）
＊１７：コバルト（ＩＩ）アセチルアセトナート
＊１８：四国化成社製２Ｅ４ＭＺ（２−エチル−４−メチルイミダゾール）
＊１９：４−ジメチルアミノピリジン
＊２０：新日鉄化学社製ＦＸ−２９３（フェノキシ樹脂）
＊２１：Ｐｉｇｍｅｎｔ ｂｌｕｅ １５：３
＊２２：Ｐｉｇｍｅｎｔ Ｙｅｌｌｏｗ １４７
＊２３：シクロヘキサノン（沸点１５０℃）
＊２４：Ｎ，Ｎ−ジメチルホルムアミド（沸点１５３℃）
＊２５：トルエン（沸点１１０℃）

* 1: ZFR-1124 manufactured by Nippon Kayaku Co., Ltd. (photosensitive carboxyl group-containing resin using a polyfunctional epoxy resin having a bisphenol F structure)
* 2: EMG-1015 manufactured by DIC (carboxyl group-containing polyimide resin, solution acid value: 863 mg KOH / g, solid content 50%)
* 3: Shin-Nakamura Chemical Co., Ltd. A-DCP (tricyclodecane dimethanol diacrylate)
* 4: jER828 manufactured by Mitsubishi Chemical Corporation (bisphenol A type epoxy resin; epoxy equivalent 180 g / eq)
* 5: HP-7200L manufactured by DIC (dicyclopentadiene type epoxy resin; epoxy equivalent 247 g / eq)
* 6: HF-1M manufactured by Meiwa Kasei Co., Ltd. (phenol novolac resin; hydroxyl group equivalent: 106 g / eq)
* 7: SN-485 (Naphthol aralkyl resin; hydroxyl group equivalent 210 g / eq) manufactured by Nippon Kayaku Epoxy Manufacturing Co., Ltd.
* 8: LA-3018 manufactured by DIC (novolac resin; hydroxyl group equivalent 75 g / eq)
* 9: LA-7054 (Novolak resin; hydroxyl group equivalent 125 g / eq) manufactured by DIC
* 10: PT-30 manufactured by Lonza Japan (phenol novolac type polyfunctional cyanate ester; cyanate equivalent 124 g / eq)
* 11: DIC's HPC-8000-65T (active ester resin; equivalent 223 g / eq)
* 12: BASF Japan Irgacure 369 (α-aminoacetophenone photopolymerization initiator)
* 13: Sakai Chemical B-30 (barium sulfate)
* 14: Admatechs SO-C2 (silica)
* 15: Showa Denko Hijilite H-42T (aluminum hydroxide)
* 16: BMI-2300 manufactured by Daiwa Kasei Co., Ltd. (condensate of phenylmethanemaleimide; softening point 70-145 ° C.)
* 17: Cobalt (II) acetylacetonate * 18: 2E4MZ (2-ethyl-4-methylimidazole) manufactured by Shikoku Kasei Co., Ltd.
* 19: 4-dimethylaminopyridine * 20: FX-293 (phenoxy resin) manufactured by Nippon Steel Chemical Co., Ltd.
* 21: Pigment blue 15: 3
* 22: Pigment Yellow 147
* 23: Cyclohexanone (boiling point 150 ° C)
* 24: N, N-dimethylformamide (boiling point 153 ° C.)
* 25: Toluene (boiling point 110 ° C)

(Carrier film, protective film)
As a carrier film, Toray Co., Ltd. Lumirror S10, FB50, and Lintec Corporation AL-5 were used. As a protective film, MA-411, MA-420, E-201F, ER-440, and FG-201 manufactured by Oji F-Tex Co., Ltd. were used.

<Measurement of thickness of carrier film and protective film>
About the carrier film and protective film of the following Tables 3-6, based on JISK7130, it measures with the micrometer in nine places about the width direction of a film, calculates each average value, and the measured value (unit) μm).

<Ra measurement of carrier film and protective film>
About the carrier film and protective film of the following Tables 3-6, the measurement of surface roughness Ra was measured using the laser microscope VK-8500 (Keyence Corporation, measurement magnification x2000 times, Z-axis measurement pitch 10nm). About the transparent film which permeate | transmits a laser beam, after performing Au sputtering process, the surface roughness Ra was measured. Moreover, about the carrier film and protective film which were subjected to the following sandblast treatment, the surface roughness Ra was measured after the sandblast treatment.

<Sandblasting>
In order to adjust the surface roughness, sandblasting was performed as follows. For the carrier film and protective film described in Tables 3 to 6 below, select a non-metallic abrasive for blasting in accordance with JIS Z 0312-1996 so that the surface state of the film becomes the desired unevenness, The conditions of the film conveyance speed, the number of treatments, and the injection pressure were set, the abrasive was struck on the surface of each film, the abrasive was washed away by water treatment and ultrasonic cleaning, and the film was dried.
About the carrier film and protective film which performed the sandblasting process, it described as "it exists" in the following Tables 3-6, and the thing which did not perform it as "absent."

(Examples 1-26, Comparative Examples 1-4)
<Production of dry film>
On the carrier films described in Tables 3 to 6 so that the film thickness after drying of the curable compositions 1 to 12 obtained above is a film thickness described in Tables 3 to 6 using a bar coater ( What was sandblasted was applied to the treated surface side). Then, it dried for 5 to 10 minutes at 70-120 degreeC (average 100 degreeC) with the hot-air circulation type drying furnace, and obtained the dry coating film which has a curable resin layer on a carrier film. Subsequently, the protective film described in Tables 3 to 6 was laminated on the resin layer at a temperature of 70 ° C. with a roll laminator, and dry films of Examples and Comparative Examples were obtained in which both surfaces were sandwiched with films. .

  The dry film of an Example and a comparative example was evaluated with the evaluation method shown below. The evaluation results are shown in Tables 3-6. In the evaluation methods shown below, the carrier film is evaluated as the first film and the protective film is evaluated as the second film.

<Heat shrinkage of dry film>
About the dry film of the Example and the comparative example, in the state which peeled the protective film, the thermal contraction evaluation of the carrier film was visually performed in the range of 100 cm x 100 cm. Judgment criteria are as follows.
○: No heat shrinkage was observed.
Δ: One streak due to heat shrinkage was confirmed in the horizontal direction with respect to the winding direction of PET.
X: Two or more streaks due to heat shrinkage were confirmed in the horizontal direction with respect to the PET winding direction.

<Peelability of protective film>
About the dry film of an Example and a comparative example, it cuts out into the square of 200x200 mm size, peels off a protective film manually from one vertex, and the component derived from the resin layer has adhered to the surface of a protective film Was judged visually, and the quality of peelability was evaluated. Judgment criteria are as follows.
○: A component derived from the resin layer is not attached to the protective film.
(Triangle | delta): The component derived from the resin layer had adhered to the protective film slightly.
X: The component derived from many resin layers had adhered to the protective film.

<Bubble generation>
CZ-8101 manufactured by MEC was used as a pretreatment for a double-sided printed wiring board on which a fine circuit having a comb-teeth pattern having a copper thickness of 10 μm and L (line: wiring width) / S (space: space width) = 10/10 μm was formed. The etching process corresponding to 0.5 μm was performed. Next, after the protective film was peeled off, the dry film of each Example and Comparative Example was laminated on the etched substrate using a batch type vacuum pressure laminator MVLP-500 (manufactured by Meiki Co., Ltd.). Lamination was carried out under the conditions of 5 kgf / cm ² , 80 ° C., 1 minute, 1 Torr, and then leveled with a hot plate press at 10 kgf / cm ² , 80 ° C., 1 minute. After laminating, air entered the boundary between the line and the space, and it was confirmed through the carrier film at 100 places whether or not bubbles were generated in the resin layer. What was evaluated by the above method was defined as “after lamination”. After observation, the evaluation of the presence or absence of generation of bubbles in the state where the resin layer was cured was regarded as “after curing”. The curing conditions are detailed in the next section. The evaluation criteria are as follows.
A: No void was confirmed.
○: 1-2 voids were confirmed.
Δ: 3 to 5 voids were confirmed.
×: 6 or more voids were confirmed.

<Method for manufacturing cured substrate>
About the dry film of an Example and a comparative example, the resin layer was hardened by three types of hardening methods, "Thermosetting", "Light and thermosetting", and "PEB (post exposure bake)", respectively. The methods of curing were described in the item <Production method of cured substrate> in Tables 3 to 6, respectively. Below, each hardening method is described.

Curing method "thermosetting"
A dry film was laminated on a circuit board with the resin layer described in each example and comparative example by the method described in <Generation of bubbles>. Thereafter, the carrier film was peeled off, and the resin layer was cured in a hot air circulation drying oven at 180 ° C. for 30 minutes and then at 190 ° C. for 60 minutes.

Curing method "light / thermosetting"
A dry film was laminated on a circuit board by the method described in <Generation of bubbles> in the resin layers described in the examples and comparative examples. Then, the solder resist pattern is exposed to 200 mJ / cm ² using an exposure device equipped with a high-pressure mercury lamp (short arc lamp) through the carrier film, and then the carrier film is peeled off, and then sprayed with a 1 wt% Na ₂ CO ₃ aqueous solution at 30 ° C. Development was performed for 60 seconds under a pressure of 0.2 Pa to obtain a resist pattern. Next, the substrate was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure amount of 1 J / cm ² , and then heat-treated at 150 ° C. for 60 minutes using a hot air circulation type drying furnace to cure the resin layer.

Curing method "PEB"
A dry film was laminated on a circuit board by the method described in <Generation of bubbles> in the resin layers described in the examples and comparative examples. Thereafter, the solder resist pattern was exposed to 500 mJ / cm ² using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp) through a carrier film. Next, after peeling off the carrier film, heat treatment (PEB treatment) was performed at 100 ° C. for 30 minutes in a hot air circulating drying furnace. The obtained substrate was developed by being immersed in a mixed aqueous solution of 3 wt% TMAH and 5 wt% ethanolamine at 35 ° C. for 3 minutes. Further, ultraviolet irradiation was performed with an energy amount of 1 J / cm ² by an ultraviolet irradiation device manufactured by ORC, and then heat treatment was performed at 170 ° C. for 60 minutes in a hot air circulation type drying furnace to cure the resin layer.

<Glossiness after curing>
About the cured substrate obtained by the method of <Preparation of cured substrate>, the glossiness at 60 ° was evaluated using a gloss meter Micro Trigloss (manufactured by Big Gardner). The smaller the value, the more lost, and the higher the value, the higher the gloss. If the degree of gloss is 40 or more, it is desirable because it is not lost.
A: Glossiness after curing is 50 or more.
○: The glossiness after curing is 40 or more and less than 50.
X: Glossiness after curing is less than 40.

<Undercut>
About the Example and comparative example which formed the resin layer with the photo and thermosetting composition, the undercut was also evaluated as follows.
On a copper-clad plate having a copper thickness of 15 μm, a CZ-8101 process manufactured by MEC was pre-processed and an etching process corresponding to 0.5 μm was performed. Next, a resist pattern (L / S = 50/50 μm, pattern on the line) was formed in accordance with the method of preparing the curing method “light / thermosetting” in the item of manufacturing the cured substrate. About the obtained board | substrate, it cut | disconnected so that it might become perpendicular | vertical with respect to a line using the precision cutting machine, and the cross-sectional length of the surface layer part and the line of a deep part was measured using the optical microscope. The evaluation criteria are as follows.
○: The difference in cross-sectional length between the surface layer portion and the deep portion line is 0 μm or more and less than 5 μm.
(Triangle | delta): The difference of the cross-sectional length of a surface layer part and a deep part line is 5 micrometers or more and less than 8 micrometers.
X: The difference of the cross-sectional length of the surface layer part and the deep part line is 8 micrometers or more.

測定不能：保護フィルムを剥離できなかったので、測定できなかった。

Inability to measure: Since the protective film could not be peeled off, it could not be measured.

From the results shown in Tables 3 to 6, it can be seen that in the case of the dry films of Examples 1 to 26, bubbles are less likely to be produced when laminating to the substrate, and the adhesiveness is excellent.
On the other hand, in the dry films of Comparative Examples 1 to 4 in which the arithmetic average surface roughness Ra of the protective film (second film) does not satisfy the range of 0.1 to 1.2 μm, the generation of bubbles was remarkable.

DESCRIPTION OF SYMBOLS 1 Dry film 11 1st film 12 2nd film 13 Resin layer

(Examples 1-8, 11-16, Reference Examples 9, 10, 17-26 , Comparative Examples 1-4)
<Production of dry film>
On the carrier films described in Tables 3 to 6 so that the film thickness after drying of the curable compositions 1 to 12 obtained above is a film thickness described in Tables 3 to 6 using a bar coater ( What was sandblasted was applied to the treated surface side). Then, it dried for 5 to 10 minutes at 70-120 degreeC (average 100 degreeC) with the hot-air circulation type drying furnace, and obtained the dry coating film which has a curable resin layer on a carrier film. Next, the protective films described in Tables 3 to 6 were laminated on the resin layer at a temperature of 70 ° C. with a roll laminator, and the dry films of Examples , Reference Examples and Comparative Examples were sandwiched between the films. Got.

The dry film of an Example , a reference example, and a comparative example was evaluated with the evaluation method shown below. The evaluation results are shown in Tables 3-6. In the evaluation methods shown below, the carrier film is evaluated as the first film and the protective film is evaluated as the second film.

<Heat shrinkage of dry film>
About the dry film of an Example , a reference example, and a comparative example, the evaluation of the thermal contraction of the carrier film was visually performed in the range of 100 cm x 100 cm in the state which peeled the protective film. Judgment criteria are as follows.
○: No heat shrinkage was observed.
Δ: One streak due to heat shrinkage was confirmed in the horizontal direction with respect to the winding direction of PET.
X: Two or more streaks due to heat shrinkage were confirmed in the horizontal direction with respect to the PET winding direction.

<Peelability of protective film>
About the dry film of an Example , a reference example, and a comparative example, it cuts out into the square of 200x200 mm size, peels off a protective film manually from one vertex, and the component derived from a resin layer adheres to the surface of a protective film It was judged visually whether peelability was good or not. Judgment criteria are as follows.
○: A component derived from the resin layer is not attached to the protective film.
(Triangle | delta): The component derived from the resin layer had adhered to the protective film slightly.
X: The component derived from many resin layers had adhered to the protective film.

<Bubble generation>
CZ-8101 manufactured by MEC was used as a pretreatment for a double-sided printed wiring board on which a fine circuit having a comb-teeth pattern having a copper thickness of 10 μm and L (line: wiring width) / S (space: space width) = 10/10 μm was formed. The etching process corresponding to 0.5 μm was performed. Next, after the protective film was peeled off, the dry film of each Example , Reference Example and Comparative Example was laminated on the etched substrate using a batch type vacuum pressure laminator MVLP-500 (manufactured by Meiki Co., Ltd.). Lamination was carried out under the conditions of 5 kgf / cm 2, 80 ° C., 1 minute, 1 Torr, and then leveled with a hot plate press at 10 kgf / cm 2, 80 ° C., 1 minute. After laminating, air entered the boundary between the line and the space, and it was confirmed through the carrier film at 100 places whether or not bubbles were generated in the resin layer. What was evaluated by the above method was defined as “after lamination”. After observation, the evaluation of the presence or absence of generation of bubbles in the state where the resin layer was cured was regarded as “after curing”. The curing conditions are detailed in the next section. The evaluation criteria are as follows.
A: No void was confirmed.
○: 1-2 voids were confirmed.
Δ: 3 to 5 voids were confirmed.
×: 6 or more voids were confirmed.

<Method for manufacturing cured substrate>
About the dry film of an Example , a reference example, and a comparative example, the resin layer was hardened by three types of hardening methods, "Thermosetting", "Light and thermosetting", and "PEB (post exposure bake)", respectively. The methods of curing were described in the item <Production method of cured substrate> in Tables 3 to 6, respectively. Below, each hardening method is described.

Curing method "thermosetting"
A dry film was laminated on the circuit board by the method described in <Generation of bubbles> in the resin layers described in each of Examples , Reference Examples and Comparative Examples. Thereafter, the carrier film was peeled off, and the resin layer was cured in a hot air circulation drying oven at 180 ° C. for 30 minutes and then at 190 ° C. for 60 minutes.

Curing method "light / thermosetting"
A dry film was laminated on the circuit board by the method described in <Generation of bubbles> in the resin layers described in each of the reference examples and comparative examples. Then, the solder resist pattern is exposed to 200 mJ / cm ² using an exposure device equipped with a high-pressure mercury lamp (short arc lamp) through the carrier film, and then the carrier film is peeled off, and then sprayed with a 1 wt% Na ₂ CO ₃ aqueous solution at 30 ° C. Development was performed for 60 seconds under a pressure of 0.2 Pa to obtain a resist pattern. Next, the substrate was irradiated with ultraviolet rays in a UV conveyor furnace under the condition of an integrated exposure amount of 1 J / cm ² , and then heat-treated at 150 ° C. for 60 minutes using a hot air circulation type drying furnace to cure the resin layer.

Curing method "PEB"
The resin layer described in Reference Example 18 was laminated with a dry film on the circuit board by the method described in <Generation of bubbles>. Thereafter, the solder resist pattern was exposed to 500 mJ / cm ² using an exposure apparatus equipped with a high-pressure mercury lamp (short arc lamp) through a carrier film. Next, after peeling off the carrier film, heat treatment (PEB treatment) was performed at 100 ° C. for 30 minutes in a hot air circulating drying furnace. The obtained substrate was developed by being immersed in a mixed aqueous solution of 3 wt% TMAH and 5 wt% ethanolamine at 35 ° C. for 3 minutes. Further, ultraviolet irradiation was performed with an energy amount of 1 J / cm ² by an ultraviolet irradiation device manufactured by ORC, and then heat treatment was performed at 170 ° C. for 60 minutes in a hot air circulation type drying furnace to cure the resin layer.

<Undercut>
About the reference example and comparative example which formed the resin layer with the photothermosetting composition, the undercut was also evaluated as follows.
On a copper-clad plate having a copper thickness of 15 μm, a CZ-8101 process manufactured by MEC was pre-processed and an etching process corresponding to 0.5 μm was performed. Next, a resist pattern (L / S = 50/50 μm, pattern on the line) was formed in accordance with the method of preparing the curing method “light / thermosetting” in the item of manufacturing the cured substrate. About the obtained board | substrate, it cut | disconnected so that it might become perpendicular | vertical with respect to a line using the precision cutting machine, and the cross-sectional length of the surface layer part and the line of a deep part was measured using the optical microscope. The evaluation criteria are as follows.
○: The difference in cross-sectional length between the surface layer portion and the deep portion line is 0 μm or more and less than 5 μm.
(Triangle | delta): The difference of the cross-sectional length of a surface layer part and a deep part line is 5 micrometers or more and less than 8 micrometers.
X: The difference of the cross-sectional length of the surface layer part and the deep part line is 8 micrometers or more.

From the results shown in Tables 3 to 6, it can be seen that in the case of the dry films of Examples 1 to 8 and 11 to 16 , bubbles are hardly generated when laminated on the base material, and the adhesiveness is excellent.
On the other hand, in the dry films of Comparative Examples 1 to 4 in which the arithmetic average surface roughness Ra of the protective film (second film) does not satisfy the range of 0.1 to 1.2 μm, the generation of bubbles was remarkable.

Claims (8)

A dry film having a first film, a second film, and a resin layer sandwiched between the first film and the second film,
The arithmetic average surface roughness Ra of the surface in contact with the resin layer of the second film is 0.1 to 1.2 μm,
The dry film, wherein the surface of the second film in contact with the resin layer is a laminate surface to a substrate.   The dry film according to claim 1, wherein a thickness A of the first film is larger than a thickness B of the second film. A dry film having a first film, a second film, and a resin layer sandwiched between the first film and the second film,
The surface in contact with the resin layer of the second film is a laminate surface to the substrate,
The dry film is characterized in that the thickness A of the first film is larger than the thickness B of the second film.   The dry film according to claim 1, which is used for vacuum laminating on a printed wiring board having a circuit.   5. The dry film according to claim 1, wherein an arithmetic average surface roughness Ra of a surface in contact with the resin layer of the first film is 0.1 μm or less.   The difference (AB) between thickness A of said 1st film and thickness B of said 2nd film is 1 micrometer or more, The any one of Claims 1-5 characterized by the above-mentioned. Dry film.   Hardened | cured material obtained by hardening | curing the resin layer of the dry film of any one of Claims 1-6. A printed wiring board comprising the cured product according to claim 7.

Images